My idea depends on the size of the butterflies - if they are larger than about 2.5 inches it wouldn't work. What about making an asymetric log cabin pattern, with the dark strips all butterfly fabric, so you would get a butterfly-rich dark diagonal with (sort-of) curvy edges surrounding diagonals of the colors? Or curvy square (!) rings...Since I am sure my description is not very clear, here are some exampleas of what I mean:
http://www.hancocks-paducah.com/Item--i-BU-CRLC (but with the "white" section done in butterflies and "dark" in multi)
http://quiltspluscolor.blogspot.com/...log-cabin.html